1. Field of the Invention
The invention relates to a sprinkling control valve, and more particularly to a portable control instrument capable of one-to-many control.
2. Description of the Related Art
As shown in FIG. 1, a conventional sprinkler system 90 for watering a lawn at a large area (such as parks, house gardens, golf courses, etc.) includes a controlling machine 91 with a plurality of control knobs 92. Moreover, a plurality of aqueducts 95 are placed under the ground at the area to be watered. A control valve 96 is provided at each of the sprinkled areas A, B, C, . . . , N. When the water is delivered by a pump 94 of a water supply unit 93 to the aqueducts 95, the duration of the on/off state of the control valves 96 is controlled by the controlling machine 91 via a cable 97. In this way, a desired effect to apply water to the sprinkling areas A, B, C, . . . , N is achieved.
However, the above-mentioned sprinkler system 90 requires professionals for installing the aqueducts 95 in advance. The work is huge and it is difficult for the installation work. Moreover, the controlling machine 91 has to be installed indoors. Moreover, the AC current passing through a transformer 99 is supplied to the controlling machine 91. Such a structure is disclosed in U.S. Pat. No. 5,293,554.
As shown in FIGS. 2 and 3, another sprinkling control system does not require a pre-installation of aqueducts 95. The sprinkling pipes 70 lie directly on the ground. A sprinkling control valve 80 is fitted to the pipe for each of different sprinkling areas A, B, C, . . . , N. The sprinkling control valve 80 includes a main body 81 with a water inlet 811 at the front end thereof as well as a water outlet 812 at the rear end thereof. The main body 81 includes a valve (not shown) for controlling the on/off state thereof and a housing 82 at the top thereof. A control panel 83 and a cover 84 are mounted on the top of the housing 82. The control panel 83 is adapted to control the activation time of the sprinkling control valves 80 according to the desired sprinkling duration for each of the areas A, B, C, . . . , N.
Regarding the above-mentioned control systems, the latter is superior to the former due to the convenient installation. However, each of the sprinkling pipes 70 has to be fitted with a sprinkling control valve 80 having the control panel 83. The inside of the control panel 83 has control unit such as microprocessor which takes up the substantial part of cost of the sprinkling control valve 80. In other words, if there are a hundred of sprinkling control valves 80, a hundred of control panels 83 must be used as well. Moreover, each of the control panel 83 requires the electric power for a smooth operation. Thus, a big battery or many small batteries (not shown) have to be installed within the housing 82 for supplying the electric power to the control panel 83. When the electric power is used up, the batteries have to be replaced. The replacement of the batteries requires the detachment of the control panel 83, thereby putting the operator to great inconvenience.
In addition, the most substantial problem is that, when there are a hundred of sprinkling control valves 80, the operator has to set the sprinkling time at each of the control panels 83 of the 100 sprinkling control valves 80. Furthermore, the control panel 83 is small so that it is difficult and inconvenient for its operation. Besides, it is not possible to integrate the data of the sprinkling control valves 80 for an effective data management. As a result, a more scientific control management is not achieved. This requires further improvement.